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Re: NTY compression proposal (fwd)



All editing errors are my own, I re-formatted the original text to better
address the points.

Forwarded message:

> Date: Sun, 18 Jan 1998 19:17:32 -0800
> From: Steve Schear <[email protected]>
> Subject: Re: NTY compression proposal

> Compression efficiency depends upon

> 1) the entropy of the input data

We are looking at selecting 100 64-bit keys out of a set of 2^64,
that is not a lot of opportunity there, given a random key generation
process, for a lot of commen patterns in the key set. If we don't have a
lot of commen patterns in the text we don't get a lot of compression.

> 2) the allowable losses

In this case we can't afford any loss.

> 3) finding an efficient algorithm to code for that entropy.

Which if we do the math requires something in the neighborhood of 33:1,
for a loss-less algorithm that's a pretty hurky boundary condition.

> I think I'm on fairly firm ground assuming that key data entropy is very=
>  high and therefore little or no compressible is feasible.

My point exactly, which would lead us to the conclusion that our requirement
of a 33:1 compression factor is not realizable.


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